Jan, If you are just going to shift the image, just the GeoTransform element should be enough. You don't need the GCPs.
On Thu, Jul 7, 2011 at 3:04 PM, Jan Hartmann <j.l.h.hartm...@uva.nl> wrote: > ** > Hi all, > > This has come up before, but I'm still struggling for an answer. I want to > rubbersheet an already projected image with control points, so as to remove > small errors.On a suggestion by Frank ( > http://lists.osgeo.org/pipermail/gdal-dev/2009-February/019775.html) I > produced a VRT file of the georeferenced image and added control points to > shift the image 1000m to the right. (see below). However, GDALWARP ignores > the control points and returns the original georeferenced image. When I > remove the georeferencing information, it does use the control points, but > returns a raw image shifted to the right. > > Is it possible to rubbersheet a georeferenced image with control points, or > am I chasing a red herring? > > Thanks, > > Jan > > <VRTDataset rasterXSize="310" rasterYSize="343"> > <SRS>PROJCS["Amersfoort / RD > New",GEOGCS["Amersfoort",DATUM["Amersfoort",SPHEROID["Bessel > 1841",6377397.155,299.1528128000008,AUTHORITY["EPSG","7004"]],AUTHORITY["EPSG","6289"]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433],AUTHORITY["EPSG","4289"]],PROJECTION["Oblique_Stereographic"],PARAMETER["latitude_of_origin",52.15616055555555],PARAMETER["central_meridian",5.38763888888889],PARAMETER["scale_factor",0.9999079],PARAMETER["false_easting",155000],PARAMETER["false_northing",463000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AUTHORITY["EPSG","28992"]]</SRS> > <GeoTransform> -8.5000000000000000e+03, 1.0000000000000000e+03, > 0.0000000000000000e+00, 2.8750000000000000e+05, 0.0000000000000000e+00, > 1.0000000000000000e+03</GeoTransform> > <Metadata /> > <Metadata domain="IMAGE_STRUCTURE"> > <MDI key="INTERLEAVE">BAND</MDI> > </Metadata> > <GCPList> > <GCP Id="" Pixel="0.0000" Line="0.0000" X="1.000000000000E+03" > Y="0.000000000000E+00" /> > <GCP Id="" Pixel="1000.0000" Line="0.0000" X="2.000000000000E+03" > Y="0.000000000000E+00" /> > <GCP Id="" Pixel="1000.0000" Line="1000.0000" X="2.000000000000E+03" > Y="2.000000000000E+03" /> > <GCP Id="" Pixel="0.0000" Line="1000.0000" X="1.000000000000E+03" > Y="1.000000000000E+03" /> > </GCPList> > <VRTRasterBand dataType="Float64" band="1"> > <Metadata /> > <ColorInterp>Gray</ColorInterp> > <SimpleSource> > <SourceFilename relativeToVRT="1">test.tif</SourceFilename> > <SourceBand>1</SourceBand> > <SourceProperties RasterXSize="310" RasterYSize="343" > DataType="Float64" BlockXSize="310" BlockYSize="3" /> > <SrcRect xOff="0" yOff="0" xSize="310" ySize="343" /> > <DstRect xOff="0" yOff="0" xSize="310" ySize="343" /> > </SimpleSource> > </VRTRasterBand> > </VRTDataset> > > _______________________________________________ > gdal-dev mailing list > gdal-dev@lists.osgeo.org > http://lists.osgeo.org/mailman/listinfo/gdal-dev > -- Best regards, Chaitanya kumar CH. /tʃaɪθənjə/ /kʊmɑr/ +91-9494447584 17.2416N 80.1426E
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